N-butanol fraction of Uncaria rhynchophylla induces apoptosis in human hepatoma cancer cells through activation of PARP

Abstract

The ability of water and ethanolic extracts isolated of Uncaria rhynchophylla (UR) to function as an anticancer agents was studied using HepG2 cells. The ethanolic UR extract was further fractionatedwith hexane, chloroform (CHCl3), ethyl acetate (EtOAc), n-butanol (n-BuOH), and water, and these fractions were subsequently investigated for anticancer activity. Among the fractions, the n-BuOH fraction induced apoptosis in a dose- and time-dependent manner, when determined by cell cycle analysis, Annexin V-FITC/PI double staining, and Hoechst 33342 staining. Moreover, the n-BuOH fraction induced apoptotic cell death by modulating the expression of caspase-7, caspase-8, and poly ADP ribose polymerase (PARP). These results indicated that the n-BuOH fraction from UR has strong anticancer activity in HepG2 cells and causes an upregulation of apoptotic proteins through the activation of PARP.